std::basic_string<CharT,Traits,Allocator>::c_str
const CharT* c_str() const; |
(until C++11) | |
const CharT* c_str() const noexcept; |
(since C++11) | |
Returns a pointer to a null-terminated character array with data equivalent to those stored in the string.
The pointer is such that the range [c_str(); c_str() + size()]
is valid and the values in it correspond to the values stored in the string with an additional null character after the last position.
The pointer obtained from c_str()
may be invalidated by:
- Passing a non-const reference to the string to any standard library function, or
- Calling non-const member functions on the string, excluding operator[], at(), front(), back(), begin(), rbegin(), end() and rend().
Writing to the character array accessed through c_str()
is undefined behavior.
|
(since C++11) |
Parameters
(none)
Return value
Pointer to the underlying character storage.
c_str()[i] == operator[](i) for every |
(until C++11) |
c_str() + i == std::addressof(operator[](i)) for every |
(since C++11) |
Complexity
Constant.
Notes
The pointer obtained from c_str()
may only be treated as a pointer to a null-terminated character string if the string object does not contain other null characters.
Example
#include <algorithm> #include <cassert> #include <cstring> #include <string> int main() { std::string const s("Emplary"); assert(s.size() == std::strlen(s.c_str())); assert(std::equal(s.begin(), s.end(), s.c_str())); assert(std::equal(s.c_str(), s.c_str() + s.size(), s.begin())); assert(0 == *(s.c_str() + s.size())); }
See also
(C++11) |
accesses the first character (public member function) |
(C++11) |
accesses the last character (public member function) |
returns a pointer to the first character of a string (public member function) |